Film-fire-prevention shutter for motion-picture machines.



1. .wELLs. FILM FIRE PREVENTION SHUTTER FOR MOTION PICTURE MACHINES.

APPLICATION FILED 001.5. 1914.

L'T. WELLS.

, mm FIRE PREVENTION saunas FOR MOTION new mcnmes.

' APPLICATION FILED 0CT.5. I9l4. 1,154,952, PatentedSept. 28, 1915.

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O I O UNITED STATES PATENT orFIoE.

JOHN T. WELLS, OF NEWPORT, KENTUCKY, ASSIGNOR TO THE EDWARDS MANUFAC-TUBING COMPANY, OF CINCINNATI, OHIO, A CORPORATION OF OHIO.

Specification of Letters Patent.

aPatented Sept. 28, 1915.

Applioationfiled October 5, 1914. Serial No. 865,181.

To all whom it may concern Be it known that I, JOHN T. WELLS, a citizenof the United States, and residing at Newport, in the county of Campbelland State of Kentucky, have invented a new and useful Improvement inFihn-Fire-Prevention Shutters for Motion-Picture Machines, of which thefollowing specification is a full disclosure.

My invention. relates to an improved fireprevention film-shutter for amoving picture machine, and its speed controlled operating means.

One of the objects of the invention is to produce "operating mechanismincreasing the safety provision.

Therefore I have invented a mechanism, speed controlled, but notdependent upon governor actuation, friction clutch, or fluid pressureprinciples, but providing positive motion transmission at a selectivesafety speed for operating the shutter. To this end a member havingspeed ratio with the film travel, and preferably a film feed roll, suchas the sprocket wheel, has escapement gear connection with a normallyclosed shutter pivot, the tension permitting the escapement at dangerspeeds, but rendering effective motion transmission at a predeterminedsafety speed. The controlling mechanism comprises pitch-mesh members,such as a tooth wheel and multi-thread worm wheel or segment wherein theangle of thread advance, the tension of the shutter closing ornormalizing device, and the speed of the tooth member in ratio with thetravel, are so correlated that, at danger speeds the intermesh isnon-effective or of an escapement nature, while at and after apredetermined safety speed the intermesh is progressive over a givenspace, rendering a predetermined-dimension motion transmission, foropening and holding open the shutter, the slowing down of the film feednormalizing the shutter, under the tension influence. The fact that thecritical speed opens and closes the shutter by gear-type transmission,renders the operation mechanically positive and accurate, and in mypreferred form shown, the elements are few, simple and effective inoperation, and readily adjustable so that the safety speed can be easilyand selectively predetermined and secured.-

The features of the invention are more fully set forth in thedescription of the accompa'nying drawings, forming a part of thisspecification, in which Figure 1 is a side elevation of a film and lightcontrolling unit of a rojecting machine, with one of the side amesremoved and some of the parts in section. F g. 2 is a plan section takenon line 22, Fig. 1. Fig. 3 is a detailed section on line 3 -3, F ig. 2.Fig. 4 is a detailed plan sect1on on line 44, Fig. 1.

The unit shown intermittently feeds th film past the focal tube 1, by anintermittently operated sprocket roller 2, which may be driven by anysuitable means, such as the ordinary type of Geneva gearing.

A back plate 3, having a light aperture 4, is pivotally mounted in theside frames and held in position by a bale 5 engaging the upper endthereof.

As there is always danger of the film becoming ignited, by the heat ofthe light rays, when it is run too slowly or stopped, I provide a fireshutter 6, which is governed by the speedof the intermittent feed roller2. This fire shutter extends over-the full area of the light aperture 4and is secured to an upright rod 7.,journaled in the back plate at 8,and int. bracket 9 attached thereto. A coil spring 10 surrounds the rod,one end bearing against the face of the fire shutter and the other endextending into an orifice in the back plate. Said spring is normallyunder tension and tends to force the fire shutter against the back plateto close the light aperture 4, said movement being made noiseless by arubber bumper 11, secured to the fire shutter. Secured to the lower endof the rod 7, opposite the shaft of the roller 2, is a cylinder 12,having a plurality of elongated spiral teeth 13, which are adapted to beengaged with a camming action by the teeth 14 of a triangular wheel 15,to expose the light aperture 4. The wheel 15 is socured to the hub ofthe roller 2 by a set screw 16 to provide for lateral adjustment. Instarting the machine one of the teeth 14 will engage the first spiraltooth 13 and rotate the cylinder 12 sufficiently to bring the secondspiral tooth into operative alinement with the plane of travel of theteeth 14, thereby commencing the opening movement of the fire shutter.

If the next tooth 14, of the wheel 15, is brought into action with thesecond spiral tooth with suflicient rapidity, the rotation of thecylinder will be continued, otherwise the coil s ring 10 will act whenthe triangular whee 15 assumes the position shown in Fig. 3, and beforethe second tooth 14 has had time to engage the second s iral tooth thetriangular wheel 15, the point of contact between the teeth 13 and 14will be varied with a corresponding variation in the speed required foreffecting an opening movement of the fire shutter. This positive orgearlike opening and closing of the shutter by speed control, andmechanically holdlng open solely under the influence of a safety filmspeed, eliminates every element of insecurity or failure of transmissionat critical speeds, and'the invention obviously Involves principles ofoperation susceptible of varlous structural and mechanical embodiment.

Having described my invention, I claim 1. In a device of the classdescribed, a normally closed fire-prevention shutter disposed inrelation to the light exposure of the film, a rotary member havlng speedratio with the film travel, and worm mechanism functioning underpredetermined speed influence of said rotary member for operating theshutter. I

2. In a device of the class described, a normally-closed fire-preventionshutter disposed in relation to the light exposure of the film.

a rotary member having speed ratio with the film travel, and wormmechanism functioning under predetermined speed influence of said rotarymember to open and hold o en the shutter at a predetermined rate of lmtravel, and means positively closing the shutter when the a rate of filmtravel decreases 3. In a device of the class described, a firereventionshutter disposed in relation to the Elm light exposure, a rotary memberhaving speed ratio with the film travel, normalizing means for theshutter, and coordinating pitch members rendered operative by the speedinfluence of said member for overcoming the normalizing tension andmoving the shutter.

4. In a device of the class described, a fireprevention shuttermovablydisposed in relation to the film light exposure, a shutter theand coiirdinatin itch members connecting said member an s utter andrendered operative or inoperative by the speed of said member.

5. In a device of the class described, a firepivogfial lmember movablein speed ratio with shutter for the film, means normally closing the.shutter, a member havin speed ratio with the film travel, and coiirinatin pitch members entraining theshutter wit saidfilm feed member, theitch angle being such that the shutter is he (1 closed at danger filmspeeds and progressively opened at safet speeds.

6. In a device of the class described, a' normally closedfire-prevention film-shutter, and operating means therefor, comprisingcoordinating pitch members rendering positive motion transmission atasafety film speed to open the shutter.

7. In a device of the class described, a normally closed fire-preventionfilm-shutter, and operating means therefor, com rising'members having apitch-mesh ren ering a predetermined dimension motion transmission at asafety film speed to open and hold open the shutter.

8. In a device of the class described, a fireprevention film-shutter, atension device normally closing said shutter, operating means thereforcomprisin members having a pitch-mesh, the tension degree of saidtension device being predetermined in relation to said pitch mesh toprevent effective motion transmission at danger film speeds, and

rendering a predetermined dimension motion transmission at a safety filmspeed.

9. In a device of the class described, a fireprevention film-shutter, atension device normally closing said shutter, operating means therefor,comprisin members having a pitch-mesh, the tenslon degree of saidtension device being predetermined in relation mission until a preetermined speed of the other member ,is attained, and thereafterrendering a predetermined dimension motion transmission for opening theshutter, said tension normally holding the shutter closed.

11. In a device of the class described, a fire-prevention film-shutter,operating means comprlsing a driving and a driven pitchmeshed member,the riving member having speed ratio with the film travel, a tensiondevice holding the shutter normally closed and influencing the saiddriven member to provide an escapement of effective motion transmissionuntil a predetermined s eed of the driving member is attained, sai itchmesh being arranged to produce a pre eterefl'ective motion transtio withthe film travel,

mined dimension motion transmission at a safety film speed for openingthe shutter and maintaining it open while said driving member isoperated at a safety film-speed.

12. In a device of the class described, a fire-prevention film-shutter,and operating means therefor, comprising a speed controlled intermeshingescapement worm-type mechanism for operating the shutter.

13. In a device of the class described, a fire-prevention film-shutter,operating means therefor, comprising a speed controlled escapementmechanism for operating the shutter, and means enabling relativeadjustment of the escapement mechanism providing a selective criticalfilm-speed for shutter operation.

14. In a device of the class described, a fire-prevention film-shutter,a pivot member therefor, a rotary member having speed rapitch-meshmembers connecting said rotary and pivot members, a tension deviceholding the shutter normally closed and influencing said pitch meshengagement to prevent effective motion transmission until apredetermined speed of the rotary member is attained, said pitch meshmembers functioning to open the shutter at a safety film speed.

15. In a device of the class described, a fire-prevention film-shutter,a pivot member therefor, a rotary member having speed ratio with thefilm travel, pitch-mesh members connecting said rotary and pivotmembers,

atension device holding the shutter normally closed and influencing saidpitch mesh engagement to prevent efiective motion transmission until apredetermined speed of the rotary member is attained, said pitchmeshmembers functioning to open the shutter at a safety film speed, andmeans providing relative adjustment determining the critical speed forshutter operation.

16., In a device of the class'described, a fire-prevention film shutter,a pivot member therefor, a worm mechanism on the pivot member, a toothedmember for engaging the worm having speed ratio with the film travel,and'tension means holding the shutter normally closed and influencingsaid worm mechanism to provide motion escapement of the tooth memberuntil a safety film speed is attained, said tooth and worm mechanismcoacting to definitely open and hold open the shutter at a predeterminedsafety film speed.

17. In a device of the class described, a fire-prevention film-shutter,tension means holding the same normally closed, a shutterpivot, a wormmember thereon, a film feed sprocket wheel and a toothed member thereonadapted to progressively engage the shut ter pivot worm threads when apredetermined sprocket wheel speed is attained to open the shutter.

18. In a device of the class described, a fire prevention film shutter,a film feed member and coordinating pitch members connecting the shutterwith the film member, the pitch angle of advance being ineffective toopen the shutter at low speeds, and functioning to open the shutter atpredetermined high speeds, said coordinatingmembers being provided withmeans functioning to hold the shutter open at said high or safety filmspeeds.

19. In a device of the class described, a normally closedfire-prevention film-shutter, a tension normalizer therefor, a memberhaving speed ratio with the film travel, and pitch type connectionbetween said .member and shutter, the angle of advance, and the tensiondegree of the normalizer, being arranged in relation to the speedvariation of said member to render the gearing action ineffective untila predetermined speed of the driver is attained, whereupon the shutteris positively opened or closed by the speed control, and mechanicallyheld open under the sole influence of a safety film speed. v

In witness whereof, I hereunto subscribe my name, as attested by the twosubscribing witnesses.

JOHN T. WELLS. Witnesses:

CLARENCE B. Fos'rnR, L. A. B -K.

